English

$\Delta\eta$-$\Delta\phi$ correlations and the ridge structure in STAR

Nuclear Experiment 2015-06-11 v1 High Energy Physics - Experiment

Abstract

Triggered di-hadron correlation studies using central Au+Au collisions at SNN\sqrt{S_{NN}} = 200 GeV in STAR revealed a novel ridge-like structure in two dimensions (Δη\Delta\eta,Δϕ\Delta\phi) for high pTp_{T} particles. A similar structure is also present in an inclusive un-triggered di-hadron correlation analysis. We study the <pTp_{T}> evolution of di-hadron correlations by increasing the lower pTp_{T} acceptance of both charged particles. A smooth evolution of data is observed and our results reproduce the triggered analysis structure near <p_{T}> = 2.7 GeV/c. We quantify the correlation structure evolution by fitting a model function. The model function emphasizes possible initial state fluctuation contributions via the use of higher harmonic model components vnv_{n} (n=1,2,3,4,5) and a remainder which is modeled via an asymmetric 2d Gaussian. The extracted parameters are compared to model predictions and p+p data at SNN\sqrt{S_{NN}} = 200 GeV and possible origins of the nearside structure are discussed.

Keywords

Cite

@article{arxiv.1209.4941,
  title  = {$\Delta\eta$-$\Delta\phi$ correlations and the ridge structure in STAR},
  author = {L. Chanaka De Silva},
  journal= {arXiv preprint arXiv:1209.4941},
  year   = {2015}
}

Comments

8 Pages, 7 Figures : Proceedings of the Winter Workshop in Nuclear Dynamics, Puerto Rico

R2 v1 2026-06-21T22:09:18.809Z